1. Field of the Invention
The present invention relates to a graphic editor for simplifying editing operations such as inputting, moving, copying, and deleting a graphic pattern or a line on a display screen, in a graphic editing system such as a CAD system, etc.
2. Description of the Related Art
Conventionally, a system for editing a functional block diagram or a circuit diagram has functions of inputting and correcting, using a graphic display, a logical element (symbol) and a signal line (line) forming a logical view of a computer. With such a system, a user is required to inform the system of a requested function (a process to be (performed).
The process information (command) of a conventional logical graphic editing system is usually given by inputting a command from a keyboard or by selecting a requested process from a menu displayed on a screen (a fixed menu, pop-up menu displayed when necessary, pull-down menu, etc.). Some commands are issued by depressing a key assigned a function (a function key).
In each case, however, at least two operation steps are required for selecting a function and a process to be performed. For example, a user must specify start and end points of a signal line after Specifying a function such as "a signal line is inputted", etc. Then, considering variations of processes, additional selections must be made.
That is, in the prior art technology, when only a symbol or a symbol and a line are to be deleted, moved, or copied, for example, either a menu or a function button is selected. When a menu is selected, for example, in addition to a selection of deleting, moving, or copying operation, either a symbol only, a line only, or an enclosed area must be specified for a deleting operation, for example. An internal process of a system in response to a selection result requires specification of either a symbol only or a symbol and a line.
Next, as the second step, to specify an object to be processed, a point or an area is specified by repositioning a cursor. As an internal process of a system, the cursor position is determined and the corresponding symbol or both the corresponding symbol and line are deleted. In a word processor, however, the process is performed only on the specified area without determining an area to be processed.
Thus, in the prior art technology, in the process of embodying a logical view in an inventor's brain using a screen, an editing process is divided into Selecting a function and an object to be processed, thus stopping his or her thinking process and reducing its efficiency by requiring double processes.
For example, when the number of symbols adds up to tens or hundreds, the number of processes in editing a graphic pattern (delete/move/copy) may add up to 200 or 300. In a graphic process in a CAD system, etc., a delete and other processes of a symbol and related input/output lines are performed. In the prior art technology, there is a problem that the object to be processed, that is, a symbol and a line must be specified separately.